Aligning Layers in Photoshop

[neil poulsen]

What's the best way to align a couple of layers in Photoshop. I took two 4x5 exposures at different shutter speeds, and I want to blend them in PS to extend my dynamic range.

I've got the images stacked, and I tried the "Align Layers" Auto menu selection. But, there's quite an obvious misalignment. Is there some trick to using this tool?

If I have to do it by hand, what's the best strategy for using rotation, etc., to align the two images?

[D. Bryant]

What's the best way to align a couple of layers in Photoshop. I took two 4x5 exposures at different shutter speeds, and I want to blend them in PS to extend my dynamic range.

I've got the images stacked, and I tried the "Align Layers" Auto menu selection. But, there's quite an obvious misalignment. Is there some trick to using this tool?

If I have to do it by hand, what's the best strategy for using rotation, etc., to align the two images?

Which version of PS are you using? Auto Align in PS CS4 has never been easier. Take a look at this video:

http://www.peachpit.com/podcasts/episode.aspx?e=EE4F349B-3132-4110-8AC0-E234C9F490EA

For CS3 take a look at this video:

http://www.peachpit.com/podcasts/episode.aspx?e=43491e20-4ee2-4783-99f5-69cff446e5a2

Don Bryant

[neil poulsen]

Boy, that was quick! Thanks for the video.

I was going to say that I know about inverting the top image and setting it's transparency to 50%. Then, fidget.

[keith english]

If the images are identical I've never even had to use auto align. Just drag it close and it will snap into place. Set transparancy to 50% first, and enlarge it to check.

[jim kitchen]

Let us say you duplicated the original image within Photoshop, and you modified the second image for whatever reason, you can do the following with instantaneous success, while both images are visible on your screen...

1. you can cut and, or create a layer within the duplicate image that you wish to modify;

2. you can change the duplicate image into a single layer by eliminating the background.


Once this layer is ready to be moved from the duplicate image to the original image within Photoshop, you should do the following:

1. place the two images side by side on your screen;

2. identify, highlight, and activate the layer in the duplicate image you wish to move;

3. hold down the "shift" key continuously;

4. drag the activated layer from the duplicate image to the original image;

5. release the "shift" key...

The dragged layer's registration within the original image will be perfect. If the registration is not perfect, you released the "shift" key too early during the transfer. You can correct the position of the active layer pixel by pixel, using your keyboard's arrow keys, if the alignment did not register correctly.

Please note, that this simple Photoshop function will only work if the images are duplicates, but this "shift" process can work if you have two completely different images. If you have two completely different images, and you wish to use this process, both images must be identical with respect to their file size, and their pixel dimensions. Photoshop should notify you whether a change will be made to the layer's properties, during the layer's transport if the properties are different, such as a change from greyscale to RGB.


jim k

[nathanm]

For a more manual approach you can also use Difference mode on the top layer and nudge to taste. Blacker pixels=more registered.

[EpicNameHere]

Does auto align or any other type of multi exposure blending function in Photoshop result in a loss of sharpness or resolution, esp. in the blended regions? Will you get "sold out" if you try to print large off an image that has been manipulated in these ways?

[nathanm]

If you use perspective or cylindrical mode it is distorting the pixels, but not if you use Position Only. It depends on your source material, what level of manipulation is needed. For large format work I've only ever used Position Only. The others seem to lend themselves to multi-shot digital work.